Short trajectory missile

ABSTRACT

Short trajectory missile comprising a missile body and a missile head separating during flight. A part of the missile head such as the front end thereof is formed of a material capable of melting due to the friction of air resistance.

United States Patent 1191 1111 3,747,533 Rossmann 11 July 24, 1973 SHORTTRAJECTORY MISSILE [56] References Cited [75] Inventor: Rudolf Rossmann,Zurich, UNITED STATES PATENTS Switzerland 2,987,999 6/1961 Robinson, Jr.et al 102 493 3,106,162 10/1963 Hagerty 102/105 [73] Assgnee' gg f fzlgxf g'g g gg 3,496,869 2 1970 Engel 102/93 3,580,179 5/1971 Gawlick etal l02/92.6 Switzerland i 1 Filed: 23, 1971 Primary Examiner-Verlin R.Pendegrass [21] AppL NO 201,521 AttorneyE. F. Wender0th,.leffrey Noltone! ill.

[30] Foreign Application Priority Data ABSTRACT Dec. 8, 1970 Switzerland18326/70 Short trajectory missile comprising a missile body and amissile head separating during flight. A part of the Cl missile headsuch as the front end] thereof is formed of [51] Int. Cl. .4 F42b 13/20a material capable of melting due to the friction of air [58] Field olSearch... lO2/49.4, 93, 92.6, resistance.

' vill lIII PATENIEDJuLwm SHEET 1 [1F 3 Fig. J

RUDOLF ROSSMAN'N, Inventor PATENIEDJULMISYS SHEET 2 0F 3 un I l l I I,

'RUDOLF ROSSMANN, Inventor mmmw Attorneys PAIENTEDJuL24|91s SHEET 3 OF 3RUDOLF ROSSMANN, Inventor 1r) IDIMM 1' Attorneys vlf(((( SI-IORTTRAJECTORY MISSILE BACKGROUND OF THE INVENTION The present inventionrelates to a short trajectory missile with a missile body and a missilehead which separates from the body during the flight of the missile. Amissile of this kind should have the same external ballisticcharacteristics for practice purposes in the range or area ofutilization as the or actual type corresponding thereto. In the brakingzone of the flight of the missile, means or agents should becomeeffective to alter the ballistic characteristics of the missile in sucha way that the flight trajectory will be considerably reduced incomparison with that of the effective or actual missile.

With a known missile of this type, the missile head is held by ballswhich are introduced into the missile head, into which a groove of themissile body projects and is held by a pin. At the time of firing asafety bolt is sheared off and the pin is thrown backwards, so that theballs become free. However, in the area of utilization these balls arepressed outwardly into the aforementioned groove by centrifugal force.Following a reduction in the centrifugal force, the balls fall out ofthe groove in the braking area, and the missile head is thrown forwardby a spring, as a result of which the missile head and missile bodyrapidly loose speed and fall to the ground.

A disadvantage with this missile is that a large number of componentsare required for the separation of the missile head, as a result ofwhich the manufacture of the missile requires considerable expenditurein time and money.

SUMMARY OF THE INVENTION It is an object of this invention to create ashort trajectory missile with a very simple and cost-saving design, suchmissile having the same external ballistic charcteristics in the rangeor area of utilization as the effective or actual missile correspondingthereto.

In accordance with the invention there is provided a short trajectorymissile comprising a missile body and a missile head capable ofseparating during the flight of the missile, wherein a part of themissile head comprises material capable of melting due to the frictionof air resistance. In a particularly advantageous embodiment, a frontend of the missile head consists of a material capable of melting as aresult of the friction of air resistance, and the missile head has ahollow space, so that after the melting of the aforementioned front end,the missile head bursts as a result of a momentary increase in airpressure into the hollow space and is separated from the missile body.

The advantages achieved with the invention lie in the fact that themissile has a very simple construction, whereby the flight range can bedetermined by a corresponding dimensioning of the missile head. Theexter- 'nal ballistic characteristics of the missile can be matched tothose of the effective or actual missle by weight and shaping of themissile body and missile head.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described byway of example with reference to the accompanying drawings in which:

FIG. ll shows a longitudinal section through the short trajectorymissile;

FIG. 2 shows the short trajectory missile of FIG. l but withoutprotective hood and plastics sheath during flight in the area of use;and

FIG. 3 shows the short trajectory missile of FIG. 2, without theseparated missile head during flight in the braking zone.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings FIG. 1shows a missile body I provided at its front end with an axially drilledchannel 2 into which extend four radially drilled holes 3, which aremutually perpendicular to each other. The missile body ll has an annularfront surface 4, which is engaged by annular ridge 6 of a missle head 5,the missile head 5 projecting into the channel 2. The missile head 5tapers to a front end 8 and has an interior hollow space 7 openingrearwardly into channel 2. The missile head 5 is thus hollow and is madefrom a material capable of melting as a result of the friction of airresistance, in this case plastic material. The missile body I issurrounded by a plastic sheath 9, which at its rear end has a guidingand sealing band 10. A protective hood Ill surrounds the missile head 5and the front end of missile body l and is secured in an annular groove112 of the plastic sheath 9.

The missile is shown while in flight in the area of utilization in FIG.2, whereby the air L striking the missile head 5 creates a ram orpressure point P and flow lines S andS FIG. 3 shows the missile while inthe braking zone whereby the unfavourable flow ratios are represented byflow lines S and 8,.

After firing, when the short trajectory missile has left the barrel, theprotective hood 11 and plastic sheath 9 are separated from the missilebody by centrifugal force. The missile, including the missile head 5,now posses a favourable, low resistance external shape, creating flowlines S, and S (see FIG. 2). At ram point P the front end 8 of themissile head undergoes, as a result of the friction of air resistance,an increase in temperature, which, for example, at a missile velocity of1,300/m/s is about 850 C and causes the missile head to melt. The wallthickness of the hollow missile head 5 is dimensioned so that thepossibility of melting through in the area of utilization :is avoided,that is to say, that the optimum missile shape is maintained in the areaof utilization.

On entry of the missile into the braking zone, the melting process hasprogressed sufficiently that the front end 8 of missile head 5 is meltedcompletely through. The opening occuring as a result of this brings outa displacement of ram point P rearwardly into hollow space '7. Themomentarily effective pressure increase therefore brought about inhollow space 7 causes the missile head 5 to burst and separate frommissile body ll. The air L flowing into channel 2 is directed radiallyoutwardly through radial holes 3, as a result of which a turbulent flowdevelops=on the external surface of the missile body. As a result theflow characteristics of the missile become very unfavourable, as shownin FIG. 3 by flow lines 8, and 8,, and air resistance is increased veryconsiderably. The missile body is thus braked very quickly so that theflight trajectory is tremedously reduced.

In this embodiment, the four radial drillings 3 are arranged mutuallyperpendicular to each other, or in other words, they are arrangedsymmetrically in relation to a plane running through the longitudinalcentre line A of the missile. With an asymmetrical arrangement inrelation to the aforementioned plane of at least two radial drillings,the stability of the missile body is additionally disturbed in thebraking zone. A resultant movement similar to a pendulum movementoccurs, so that the flight trajectory is even further reduced.

I claim: 1. A short trajectory training missile comprising: a missilebody; a missile head separably attached to the forward end of saidmissile body; said attached missile body and missile head having anexterior shape to produce external ballistic characteristics within therange of desired utilization identical to those of a correspondingactual missile; said missile having means for causing said missile headto separate from said missile body upon passage of said missile fromsaid range of utilization, thereby substantially altering the ballisticcharacteristics of said missile, and for imparting a rapid braking ofthe trajectory of said missile; said means comprising a hollow space onthe interior of said missile head, and a forward end of said missilehead closing said hollow space, said forward end being formed of amaterial capable of being melted through by the friction of airresistance upon the passage of said missile from said range ofutilization, whereby said hollow space is subjected to an instantaneousair pressure increase, and said missile head being formed of a materialcapable of bursting under the force of such interior air pressureincrease.

2. A missile is claimed in claim 1, further comprising an axial channelextending into said missile body from the forward end thereof, saidmissile head extending into said axial channel, said hollow spacecommunicating with said axial channel and at least one radial holeextending outwardly through said missile body from said axial channel tothe exterior of said missile, whereby when said forward end of saidmissile head melts, air passes through said hollow space, inJo saidaxial channel, and outwardly through said at least one radial hole,thereby creating increased rapid braking of the trajectory of saidmissile.

3. A missile as claimed in claim 2, wherein said at least one radialhole comprises a plurality of radial holes symmetrically spaced aroundsaid missile body.

4. A missile as claimed in claim 2, wherein said at least one radialhole. comprises a plurality of radial holes asymmetrically spaced aroundsaid missile body.

5. A missile as claimed in claim 2, wherein said at least one radialhole comprises four radial holes spaced around said missile body.

1. A short trajectory training missile comprising: a missile body; amissile head separably attached to the forward end of said missile boDy;said attached missile body and missile head having an exterior shape toproduce external ballistic characteristics within the range of desiredutilization identical to those of a corresponding actual missile; saidmissile having means for causing said missile head to separate from saidmissile body upon passage of said missile from said range ofutilization, thereby substantially altering the ballisticcharacteristics of said missile, and for imparting a rapid braking ofthe trajectory of said missile; said means comprising a hollow space onthe interior of said missile head, and a forward end of said missilehead closing said hollow space, said forward end being formed of amaterial capable of being melted through by the friction of airresistance upon the passage of said missile from said range ofutilization, whereby said hollow space is subjected to an instantaneousair pressure increase, and said missile head being formed of a materialcapable of bursting under the force of such interior air pressureincrease.
 2. A missile is claimed in claim 1, further comprising anaxial channel extending into said missile body from the forward endthereof, said missile head extending into said axial channel, saidhollow space communicating with said axial channel and at least oneradial hole extending outwardly through said missile body from saidaxial channel to the exterior of said missile, whereby when said forwardend of said missile head melts, air passes through said hollow space,inJo said axial channel, and outwardly through said at least one radialhole, thereby creating increased rapid braking of the trajectory of saidmissile.
 3. A missile as claimed in claim 2, wherein said at least oneradial hole comprises a plurality of radial holes symmetrically spacedaround said missile body.
 4. A missile as claimed in claim 2, whereinsaid at least one radial hole comprises a pluralIty of radial holesasymmetrically spaced around said missile body.
 5. A missile as claimedin claim 2, wherein said at least one radial hole comprises four radialholes spaced around said missile body.